Volatile material dispenser

ABSTRACT

A volatile material dispenser includes a base that houses a printed circuit board, a stand assembly that is coupled with the base, the stand assembly including a platform, a stand that extends from the platform, and a manifold that extends from the stand, the manifold containing a circular piezoelectric element. The dispenser further includes a shroud that is coupled with the stand assembly and defines a chimney, and a refill comprising a wick, the refill being removably coupled with the manifold. The manifold includes a cylindrical wall that extends upward from the manifold, a spring is disposed within the manifold and is coaxial with the cylindrical wall, and a top end of the spring is wrapped around the cylindrical wall and a bottom end of the spring applies a force against the piezoelectric element.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

The present disclosure relates generally to volatile material dispensersfor emitting volatile materials and, more particularly, to volatilematerial dispensers having a piezoelectric element and lightingassembly.

2. Description of the Background of the Disclosure

Various volatile material dispensers are known in the art, most of whichdeliver fragrance to the surrounding environment by a variety ofdifferent mechanisms. For example, some dispensers spray a volatilecontaining a fragrance into the surrounding environment, while otherdispensers allow for the evaporation of a volatile containing afragrance into the surrounding environment. Such volatile materialdispensers generally include a housing with a refill inserted therein.The refill generally includes a container for holding a volatilematerial, and the volatile material may include various components suchas aroma chemicals, water, solvents, surfactants, alcohols, and/or othercomponents. Some refills include a wick in contact with the volatilematerial and extending out of the refill to carry the volatile materialout of the refill. Other refills include a gel-like substance that isemitted through a semi-permeable membrane. Regardless of the type ofrefill, the refill may be inserted into a volatile material dispenserhaving a heater, a piezoelectric element, an aerosol actuator, and/orany other diffusion element that may assist in delivering the volatilematerial.

However, many prior art dispensers do not distribute volatile materialsin a uniform or accurately dosed fashion. Further, many dispensers failto include visual feedback to a user regarding the amount or quantity ofvolatile that is being or has been dispensed by the volatile materialdispenser. As such, there is a need for a volatile material dispenserhaving a mechanism that accurately disperses a volatile while providingadjustable, visual feedback to a user.

SUMMARY OF THE INVENTION

According to a first aspect, a volatile material dispenser includes abase that houses a printed circuit board and a stand assembly that iscoupled with the base via one or more fastening mechanisms. The standassembly includes a platform, a stand that extends from the platform,and a manifold that extends from the stand. A refill is removablycoupled with the manifold, the refill comprising a wick that defines awick diameter (DW). The manifold houses a piezoelectric element thatdefines an array of apertures and the array defines an array diameter(DA). A ratio of the wick diameter and the array diameter (DW/DA) isgreater than 1.0.

According to some embodiments, the base further includes a low voltageport that is capable of being electrically coupled with a low voltagepower source. According to some embodiments, a plurality of LEDs arecoupled with the printed circuit board. In some embodiments, theplurality of LEDs are configured to display a first color and a secondcolor. In some embodiments, the manifold comprises a chassis and acrown, the crown comprising a cylindrical wall that defines a channeland a shroud is coupled to the stand assembly, which defines a chimneythat is coaxial with the channel. In some embodiments, the piezoelectricelement includes a piezoelectric plate, and the piezoelectric plateincludes a dome, the array of apertures being entirely disposed alongthe dome. In some embodiments, the array of apertures are disposed in acircular array. In some embodiments, the dispenser further includes alimit switch disposed along the PCB and the limit switch preventsactivation of the piezoelectric element unless a shroud is coupled withthe stand assembly.

According to another aspect, a volatile material dispenser includes abase that houses a printed circuit board and a stand assembly that iscoupled with the base. The stand assembly includes a platform, a standthat extends from the platform, and a manifold that extends from thestand, the manifold containing a circular piezoelectric element. Thedispenser further includes a shroud that is coupled with the standassembly and defines a chimney, and a refill comprising a wick, therefill being removably coupled with the manifold. The manifold includesa cylindrical wall that extends from the manifold. A spring is disposedwithin the manifold and is coaxial with the cylindrical wall. A top endof the spring is wrapped around the cylindrical wall and a bottom end ofthe spring applies a force against the piezoelectric element.

In some embodiments, the spring has a spring wire with a diameter ofbetween about 0.50 mm and about 0.60 mm. In some embodiments, a firsttab and a second tab depend from the manifold to receive a refill. Insome embodiments, the first and second tabs include first and secondcatches that extend inward, and are capable of engaging with a rim ofthe refill. In some embodiments, the spring causes a force to be exertedagainst a head of a refill when the refill is inserted into themanifold. In some embodiments, the piezoelectric element defines anarray of apertures and the array defines an array diameter (DA), and aratio of a wick diameter (DW) and the array diameter (DW/DA) is about1.1. In some embodiments, the manifold defines a head cavity, and aplurality of ribs extend from the manifold into the head cavity. In someembodiments, the manifold comprises a chassis and a crown that is snapfit to the chassis. In some aspects, a plurality of ribs extend along aside surface of the crown that are physically engaged with an undersideof the shroud.

According to yet another aspect, a volatile material dispenser includesa base that houses a printed circuit board, the base defining a sidewalland including at least one button that projects from the sidewall, and alow voltage port. The dispenser further includes a stand assembly thatis coupled with the base. A shroud has a frustoconical sidewall with alower edge that extends from an upper edge of the base, the shrouddefining a chimney. A refill comprises a wick and is removably coupledwith the stand assembly. At least one button is disposed about 180degrees offset from the low voltage port.

In some embodiments, the dispenser further includes a spring within amanifold of the stand assembly, the spring being operable to engage withthe piezoelectric element to maintain continuous contact between thewick and the piezoelectric element. The spring has a spring wire with adiameter of between about 0.50 mm and about 0.60 mm. In someembodiments, the piezoelectric element defines an array of apertureshaving an array diameter (DA). The wick defines a wick diameter (DW) anda ratio of the wick diameter to the array diameter (DA/DW) is greaterthan 1.0.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, top, and right isometric view of a volatile materialdispenser in accordance with the present disclosure;

FIG. 2 is a front elevational view of the volatile material dispenser ofFIG. 1;

FIG. 3 is a rear elevational view of the volatile material dispenser ofFIG. 1;

FIG. 4 is a left side elevational view of the volatile materialdispenser of FIG. 1;

FIG. 5 is a top plan view of the volatile material dispenser of FIG. 1;

FIG. 6 is a bottom plan view of the volatile material dispenser of FIG.1;

FIG. 7 is a front, top, and right isometric view of an internal standand a base of the volatile material dispenser of FIG. 1 with a shroudhaving been removed for clarity;

FIG. 8 is a right side elevational view of the stand and base of FIG. 7;

FIG. 9 is a front elevational view of the stand and base of FIG. 7;

FIG. 10 is a front, top, and right isometric view of a refill for usewith the volatile material dispenser of FIG. 1;

FIG. 11 is a front, top, and right isometric view of the refill of FIG.10 with a cap having been removed;

FIG. 12 is a side cross-sectional view of the refill taken through line12-12 of FIG. 11;

FIG. 13 is a cross-sectional view of the volatile material dispensertaken through line 13-13 of FIG. 5;

FIG. 14 is a cross-sectional view of the volatile material dispensertaken through line 14-14 of FIG. 5;

FIG. 15 is a front, top, and left isometric view of various electricalcomponents of the volatile material dispenser of FIG. 1, including apiezoelectric element;

FIG. 16 is a top plan view of a printed circuit board and some of theelectrical components shown in FIG. 15;

FIG. 17 is a front, top, and right isometric view of the piezoelectricelement shown in FIG. 16;

FIG. 18A is a cross-sectional view of the piezoelectric element takenthrough line 18-18 of FIG. 17;

FIG. 18B is a schematic illustration of a circular-shaped array ofapertures along the piezoelectric element of FIG. 17;

FIG. 18C is a schematic illustration of an oval-shaped array ofapertures along the piezoelectric element of FIG. 17;

FIG. 19 is a detail view of an upper portion of the internal stand ofFIG. 14;

FIG. 20 is a detail view of the upper portion of the internal stand ofFIG. 19 with the refill of FIG. 10 inserted into a manifold of thestand;

FIG. 21 is a line graph illustrating the results of various tests ofsprings having varying thicknesses;

FIG. 22 is a line graph illustrating the results of a piezoelectricelement and various tests comparing spring force against a resultantfragrance output;

FIG. 23 is a front, right, and top view of the stand and base of FIG. 7with the refill of FIG. 10 being inserted into a head cavity thereof;

FIG. 24 is a front, right, and top view of the stand and base of FIG. 23with the refill having been inserted into an engaged configuration; and

FIG. 25 is a front, right, and top view of the stand and base of FIG. 23with a shroud being engaged with the base.

DETAILED DESCRIPTION

The present disclosure is directed to volatile material dispensers ordiffusers and methods of emitting volatile materials therefrom. Whilethe present disclosure may be embodied in many different forms, severalspecific embodiments are discussed herein with the understanding thatthe present disclosure is to be considered only an exemplification ofthe principles of the disclosure, and it is not intended to limit thedisclosure to the embodiments illustrated. Throughout the disclosure,the terms “about” and “approximately” refer to a range of values ±5% ofthe numeric value that each term precedes.

The volatile material dispensers or diffusers disclosed herein aremultisensory devices that use a piezoelectric engine to create and ejectmicro droplets of liquid fragrance into the surrounding environment. Thevolatile material dispensers are configured to accept a replaceablefragrance oil bottle or refill. The dispensers are further configured torun on low voltage, and feature a fragrance intensity selector thatprovides visual feedback to a user in the form of a glowing light. Thedispenser includes a shroud, a stand assembly, and a base thatcollectively house control buttons, a power connector, lights, and apiezo engine. The shroud is primarily decorative and provides a lighttransmission shade. Before a first use of the volatile materialdispenser, the shroud is removed to insert a fragrance oil bottle orrefill into the stand assembly.

Still further, the volatile material dispensers disclosed herein includeimprovements to a piezo plate-to-wick interface, which, through testing,has been found to increase system performance and consistency.Specifically, testing has revealed a sensitivity and variations inconsistency based upon a downward contact force of the piezo plate and atop of the wick. For example, a constant force provides a moreconsistent output and minimized variance. Through testing, it has alsobeen determined that force differences can create variances in outputrate as a result of changing load conditions on the piezo plate. Toohigh of a downward load onto the piezo plate has been found to dampen anamplitude of mechanical vibration of the piezo plate, which can minimizedroplet output. Conversely, too light of a downward force has been foundto limit the plate-to-wick interface contact, which has been found toresult in high, undamped output. This is likely because under suchcircumstances, contact between the piezo plate and the wick can be lostentirely.

Referring now to the drawings, FIGS. 1-7 depict a volatile materialdispenser 50 embodying aspects of the present disclosure. The dispenser50 may be adapted to accommodate a refill 52 (see FIGS. 10-12) anddispense a volatile material in the form of water and/or fragranced oilfrom the refill 52. Referring specifically to FIGS. 1 and 2, thedispenser 50 includes a shroud or cover 54 and a base 56. The shroud 54defines a lower edge 58 that interfaces with an upper edge 60 of thebase 56. A sidewall 62 of the shroud 54 extends upward from the loweredge 58 toward a lip 64 at an upper end 66 of the shroud 54. Thesidewall 62 of the shroud 54 defines a frustoconical lower portion 68and a spline-shaped upper portion 70, when viewed in cross-section. Aplurality of ridges or design features 72 are provided along an outersurface 74 of the shroud 54. Any number of design features 72 may beprovided along the outer surface 74 of the shroud 54. The lower portion68 and the upper portion 70 of the shroud 54 intersect at a roundedshoulder 76, from which the upper portion 70 extends toward a chimney 78that is centered about a central longitudinal axis 80 (FIG. 2) of thedispenser 50. The chimney 78 is defined as the portion interior to thelip 64. In some embodiments, the shroud 54, and the base 56 comprisepolypropylene (PP), however, the shroud 54 and the base 56 may comprisea wide variety of polymeric materials.

Still referring to FIGS. 1 and 2, the sidewall 62 along the upperportion 70 extends from the shoulder 76 toward the lip 64. Referring toFIG. 1, a flange 84 of the shroud 54 extends downward from the lip 64toward the longitudinal axis 80 and into the chimney 78. The angle atwhich the flange 84 extends downward from the lip 64 is best illustratedin the cross-sectional views of FIGS. 13 and 14. Referring specificallyto FIG. 2, while the chimney 78 may define a variety of diameters, thechimney 78 is illustrated having a diameter D1 that is about 30% of awidest diameter D2 of the shroud 54 taken at the lower edge 58 thereof.In some embodiments, the diameter D1 may be between about 5% and about60% of the diameter D2, or between about 10% and about 45% of thediameter D2, or between about 15% and about 35% of the diameter D2. Insome embodiments, the diameter D1 is about 10%, or about 20%, or about30%, or about 40%, or about 50% of the diameter D2.

Referring again to FIGS. 1 and 2, the base 56 also defines a sidewall 90that extends from the upper edge 60 of the base 56 downward, toward abottom wall 92 thereof. A plurality of feet 94 extend downward from thebottom wall 92, and are provided to allow the dispenser 50 to rest upona flat surface (not shown). The sidewall 90 of the base 56 is generallycurved, and extends from the upper edge 60 downward and inward, towardthe longitudinal axis 80. The sidewall 90 of the base 56 may define aradius of curvature along a portion of the sidewall 90. Still further, afirst button 96, a second button 98, and a third button 100 extend fromthe base 56 outward, away from the longitudinal axis 80. The firstbutton 96, the second button 98, and the third button 100 may be usedfor a variety of purposes, and may have a variety of differentfunctions, as discussed hereinafter below.

Referring to FIG. 2, the first button 96, the second button 98, and thethird button 100 may be provided along the base 56 of the dispenser 50.The first button 96 may be a power button that allows a user to turn thedispenser 50 on and off. The second button 98 may be a fragrancestrength adjusting button that allows a user to cycle through settingsof the dispenser 50. For example, the user may be able to switch betweena low setting, a medium setting, and a high setting. A plurality oflight indicators 102 may be visible through the base 56 adjacent orbelow the second button 98. The light indicators 102 may provide visualfeedback to a user regarding the strength or intensity of the chosensetting. In the illustrated embodiment, there are three of the lightindicators 102. When the low setting is selected, one of the lightindicators 102 may be illuminated; when the medium setting is selected,two of the light indicators 102 may be illuminated; and when the highsetting is selected, three of the light indicators 102 may beilluminated. The third button 100 may be a light illumination buttonthat, when pressed by a user, cycles through various light brightnesssettings and color settings.

A user can select an option for light and/or color based on personalpreference. Further, in some embodiments, after being turned on via thefirst button 96, the dispenser 50 may run for a pre-determined amount oftime, e.g., 8 hours, and may subsequently enter into a sleep mode for apre-determined amount of time, e.g., 16 hours. The dispenser 50 mayrepeat this cycle every 24 hours unless manually turned off via thefirst button 96 by a user. In some embodiments, the dispenser 50includes an automatic shut-off function that deactivates the dispenser50 after a particular period of time, for example, after seven 24-hourcycles, i.e., one week. In some embodiments, a limit switch (not shown)may be provided along the base 56 which only allows the dispenser 50 tobe activated when the shroud 54 is engaged with the base 56.

Referring now to FIG. 3, a rear view of the dispenser 50 is shown. Asillustrated in the rear view, the dispenser 50 further includes a lowvoltage receptacle or port 104 for receiving a low-voltage electricalconnector of a low voltage wire, such as a USB cord (not shown). In someembodiments, electrical prongs, a cord, or another suitable electricalconnector may be electrically coupled with the dispenser 50 so as toallow electrical power to be provided to the dispenser 50. FIG. 4illustrates a left side of the dispenser 50. The buttons 96, 98, 100 andthe port 104 extend outward from the sidewall 90 of the base 56 andcause interruptions of the sidewall 90. As a result, the sidewall 90 ofthe base is rotationally symmetrical, but the entire base 56 issymmetric about a plane 13-13 (see FIG. 5) that bisects the secondbutton 98 and the port 104. Additional features may be provided withinor along the shroud 54 and/or the base 56. Further, additional bodiesdefining one or more sidewalls (not shown) may be provided between,above, or below the base 56 and the shroud 54.

Referring now to FIG. 5, a top view of the dispenser 50 is depicted. Thechimney 78 is shown in greater detail, which is centered along thelongitudinal axis 80. A piezoelectric assembly 110 is shown within thechimney 78, which is also centered along the longitudinal axis 80. Anannular piezoelectric element 112 is also visible through the chimney78, the piezoelectric element 112 defining a circular rim of thepiezoelectric assembly 110. The piezoelectric element 112 includes acentral aperture 114 through which liquid volatile within the refill isdispersed when the dispenser 50 is activated. When the dispenser 50 isactivated, a stream of the volatile is dispensed through the chimney 78of the shroud 54 and out of the dispenser 50, as discussed in greaterdetail hereinafter below.

Referring now to FIG. 6, the bottom wall 92 of the base 56 is shown ingreater detail. The plurality of feet 94 extend from the bottom wall 92.The plurality of feet 94 are provided in a generally circular shape,with alternating circular and elongate feet 94. Alternativeconfigurations or shapes of the feet 94 are contemplated, while in someembodiments additional structure may be included in addition to the feet94. Still further, in some embodiments, there are no feet 94 or othertypes of stability mechanisms that retain the dispenser 50 in an uprightconfiguration. As further illustrated in FIG. 6, the second button 98and the port 104 are provided 180 degrees offset from one another aboutthe longitudinal axis 80. The first button 96, the second button 98, andthe third button 100 are also equally spaced apart from one another.Alternative configurations of the port 104 and the buttons 96, 98, 100are also contemplated.

Referring now to FIGS. 7-9, a stand assembly 116 of the dispenser 50 isshown, with the shroud 54 having been removed for clarity. The standassembly 116 includes a platform 118, a stand 120, a refill chassis 122,and a crown 124. The refill chassis 122 and the crown 124 define amanifold 126 that retains the refill 52 and the piezoelectric assembly110. The platform 118 extends upward from the base 56 and is inset fromthe sidewall 90 thereof. A plurality of retention protrusions 128 extendoutward from the platform 118, which operate to engage the shroud 54when it is coupled with the base 56. The retention protrusions 128 are aform of retention mechanism that couples the shroud 54 with the base 56.Alternative retention mechanisms may include elements that cause a snapfit, a friction fit, or an interference fit. The platform 118 ispermanently coupled with the base 56 via a plurality of fasteners 130(see FIG. 13), the channels for which are covered by the feet 94 afterassembly thereof. The fasteners 130 are a form of fastening mechanism,additional examples of which include rivets, nails, bolts, or cables.

The platform 118 defines an outer cylindrical surface 132 that extendsupward to a corner 134. An angled surface 136 extends inward anddownward from the corner 134, toward a well 138 defined within a centralportion 140 of the platform 118. A slot 142 is defined within the angledsurface 136 along a front portion 144 of the platform 118. The slot 142may be included to aid in the insertion of the refill 52 into anoperable configuration. The well 138 may include additional featuresthat aid in retaining the refill 52 or another component. For example,the well 138 of the platform 118 may be sized and shaped to retain a cap146 (see FIG. 10) of the refill 52 after the cap 146 has been removedfrom the refill 52.

Still referring to FIGS. 7-9, the stand assembly 116 includes the stand120, which extends upward from the platform 118 along a rear portion 148thereof. The stand assembly 116 comprises a unitary piece that extendsupward from the platform 118 toward the manifold 126, which extendsinward, and aligns with the longitudinal axis 80. Elements of the standassembly 116 may also comprise polypropylene or another type ofpolymeric material. As noted above, the manifold 126 includes the crown124 and the refill or chassis 122, which extends downward from the crown124. The chassis 122 includes the first and second tabs 150 that dependdownward to retain an annular rim 152 (see FIG. 11) of the refill 52. Aswill be discussed in greater detail hereinafter below, the first andsecond tabs 150 may be formed to flex outward when the refill 52 islaterally inserted into the chassis 122 until the rim 152 of the refillengages with the tabs 150.

The refill 52 may be removed from the tabs 150 by a user grabbing therefill 52 and laterally pulling the refill down. In some embodiments,the forces required for insertion and removal of the refill 52 are lowenough to simply allow for lateral insertion and removal. However, insome embodiments, the refill 52 may be removed by squeezing the tabs 150to deflect the tabs 150 outward, thereby releasing the rim 152 fromengagement therewith. In some embodiments, the refill 52 may bedisengaged by rotating the refill 52 such that threading 154 (see FIG.11) allows the refill to be rotated and translate downward, away fromthe crown 124, for removal from the manifold 126. Alternative removalmechanisms may be implemented, such as one or more buttons (not shown)that could be depressed to cause the refill 52 to be released from thechassis 122.

With continued reference to FIGS. 7-9, the crown 124 extends upward fromthe chassis 122 and defines a generally frusto-conical side surface 156that terminates at a top surface 158. A plurality of ribs 160 areradially disposed along the side surface 156, which may be formed to aidin physical engagement with an underside 162 (see FIG. 13) of the shroud54. The ribs 160 are spaced apart about the longitudinal axis 80. Acylindrical wall 164 extends upward from the top surface 158 of thecrown 124, the cylindrical wall 164 having a center that is coaxial withthe longitudinal axis 80. The cylindrical wall 164 is also coaxial withthe chimney 78 defined by the shroud 54. The cylindrical wall 164 isaligned with the second button 98 and the port 104, i.e., the plane13-13 (see FIG. 5) extends through all of the cylindrical wall 164, thesecond button 98, and the port 104. While the shroud 54 generallycomprises radial symmetry notwithstanding the design features 72, theplatform 118, the stand 120, and the manifold 126 may be characterizedas being symmetric about the plane 13-13 that intersects the secondbutton 98 and extends through the longitudinal axis 80.

Referring now to FIGS. 10-12, the refill 52 is shown in greater detail.The refill 52 comprises a cap 146 and a container 170 defining a body172, a shoulder 174, and a head 176. The body 172 comprises acylindrical outer wall 178 that extends upward from a lower wall 180thereof to the shoulder 174. The head 176 extends upward from theshoulder 174 and defines a finish 182. The head 176 joins the body 172at the shoulder 174. The refill 52 further includes a cap 146 that isthreadably coupled with the threading 154 (see FIGS. 11 and 12) disposedalong a neck 184 of the refill 52. Referring to FIG. 12, the container170 holds a volatile material therein, and the container 170 is adaptedto be retained within the dispenser 50. A wick holder or plug 186 isdisposed within the neck 184 for holding a wick 188 with a first end ofthe wick 188 in contact with the volatile material and a second end ofthe wick 188 extending out of the container 170 through the neck 184. Inillustrative embodiments, the wick 188 may be formed of extruded fibersthat are bundled together into the shape of a rod.

Still referring to FIG. 12, the wick 188 may be formed of rope or one ormore cotton cords. The wick 188 comprises an upper wick 192 and a lowerwick 194. The upper wick 192 has different properties than the lowerwick 194, however, in some embodiments, the upper wick 192 and the lowerwick 188 have the same properties. In a preferred embodiment, the upperwick 192 is pliable and/or fibrous, while the lower wick 194 may besintered or more rigid than the upper wick 192. The upper wick 192 mayhave properties that allow the upper wick 192 to deform into thepiezoelectric assembly 110. The lower wick 194 includes a lower end 196disposed adjacent and spaced apart from the lower wall 180, and has anupper end 198 that is engaged with the upper wick 192. The upper wick192 is nested within a wick cavity 200 at the upper end 198 of the lowerwick 194. An upper cambered or angled surface 202 surrounds an innerperiphery of the wick cavity 200. The upper angled surface 202 may aidin alignment of the upper wick 192 within the wick cavity 200 duringassembly of the refill 52. The upper wick 192 is snugly retained by theplug 186 and has a distal end 204 that extends upward, out of thecontainer 170. The wick 188 may be formed in any suitable shape or ofany suitable material, however, the upper wick 192 is preferably morepliable than the lower wick 194. The plug 186 is retained within theneck 184 of the refill 52 by an interference fit, a friction fit, or inany other suitable manner that holds the plug 186 in place within theneck 184.

Still referring to FIG. 12, the shoulder 174 of the container 170extends upward to the finish 182 and the neck 184 of the head 176. Thethreading 154 circumscribes the neck 184 and extends outward therefrom.The annular rim 152 also circumscribes the finish 182, which may be usedto engage the refill 52 with the depending tabs 150 of the chassis 122.The lower wall 180 of the refill 52 is generally concave and extendsupward, toward the wick 188. An air hole 208 (see FIG. 11) is providedwithin the plug 186 to allow air to enter into a cavity 210 of therefill 52 as liquid (not shown) is dispersed out of the refill 52 intothe surrounding atmosphere. Although a refill 52 is shown and describedwith particularity, it is contemplated that any type of refill may beused with variations of the dispensers described herein. For example, arefill with a flexible container may be utilized. Still further, thedelivery system (i.e., the wick) may be different and/or the size and/orthe shape of the container 170 may be different than those describedherein.

The volatile material disposed in the container 170 may be any type ofvolatile material adapted to be dispensed into an environment. Forexample, the material within the container 170 may include a cleaner, aninsecticide, an insect repellant, an insect attractant, a disinfectant,a mold or mildew inhibitor, a fragrance, a disinfectant, an airpurifier, an aromatherapy scent, an antiseptic, an odor eliminator, apositive fragrancing volatile material, an air-freshener, a deodorizer,or the like, and combinations thereof. Additives may be included in thevolatile material, such as, for example, fragrances and/orpreservatives. In fact, any fluid may be provided within the container170.

Referring now to the cross-sectional views of FIGS. 13 and 14, internalcomponents of the dispenser 50 are shown in greater detail. Referring toFIG. 13, the base 56 is shown being connected with the stand assembly116 via one of the fasteners 130. The fastener 130 is disposed within afastener channel 214 that is covered from view by one of the feet 94after the stand assembly 116 has been fastened to the base 56. In thepresent embodiment, there are three fasteners 130 that secure the base56 with the stand assembly 116, however, only a single fastener 130 isshown in the cross-section of FIG. 13.

A printed circuit board (PCB) 216 is shown intermediate the base 56 andthe stand assembly 116. A plurality of light emitting diodes (LEDs) 218are shown electrically coupled with the PCB 216, the plurality of LEDs218 being disposed above the PCB 216. In some embodiments, the pluralityof LEDs 218 are disposed above and below the PCB 216. In someembodiments, some of the LEDs 218 are disposed adjacent the front, rear,and sides of the dispenser 50. As noted above, the LEDs 218 are intendedto be used to emit light through the shroud 54 depending on the chosensetting, which can vary based on user preference. The LEDs 218 mayalternatively be positioned in any suitable location within thedispenser 50. The one or more LEDs 218 may indicate that the dispenser50 is on or off, may provide an alert, and/or may provide any othersuitable indicator for a user. As noted above, a color and/or abrightness of the LEDs 218 may be adjusted depending on a desiredbrightness and/or color of light to be emitted through the shroud 54.

For example, a first one of the LEDs 218 may illuminate a first colorwhen the dispenser 50 is in a “Low” setting, a second one of the LEDs218 may illuminate a second color when the dispenser 50 is in a “Medium”setting, and a third one of the LEDs 218 may illuminate a third colorwhen the dispenser 50 is in a “High” setting. The third LED 218 mayilluminate by itself in the high setting, or the lighting may beadditive, such that both that first LED 218, the second LED 218, and thethird LED 218 illuminate in the high setting, in which they may have thesame or different colors and/or intensities. Alternatively, the firstLED 218 may be illuminated when the dispenser 50 is plugged in but noton, and the second LED 218 may be illuminated when the dispenser 50 isplugged in and turned on. The dispenser 50 may include one or moreseparate openings in the shroud 54 or translucent portions of the shroud54 to permit passage of the light emitted by each LED 218.

Still referring to FIG. 13, the second button 98 is shown protrudingthrough the base 56. While the second button 98 is shown and referred tohereinafter below, the first button 96 and the third button 100 have anidentical setup and functionality. The second button 98 is shownadjacent a switch 220, the switch 220 being operable to be adjustedbetween various settings of the dispenser 50. The switch 220 may be apush button switch that, when depressed, may cause the dispenser 50 toinitiate one or more functions, such as turning the dispenser 50 on oroff, causing an adjustment in the amount of fragrance that is dispensed,or adjusting the color or brightness of one or more of the LEDs 218. Theswitch 220 that is visible in FIG. 13 is one of a plurality of switches220 that are visible in FIG. 16. The switches 220 may be the sameswitches, or the switches 220 may be different.

While the dispenser 50 is disclosed as having particular switches, oneskilled in the art will appreciate the dispenser may include any numberof switches and/or may include any suitable types of switches, forexample, timing switches, on/off switches, setting switches, switchescontrolling another component within the assembly, such as a heater or afan, and/or any other suitable switches.

Still referring to FIG. 13, the stand assembly 116 is shown in crosssection, and the components that are disposed therein are visible. Awire tube 222 is shown, which extends from a terminal 224 that isdisposed along the PCB 216, through the stand 120, and into the chassis122. First and second wires 226 are disposed within the wire tube 222,which are electrically connected to the terminal 224 and to thepiezoelectric assembly 110, which is disposed within the crown 124 ofthe stand assembly 116. The stand 120 is fixedly coupled with thechassis 122, which is also fixedly coupled with the crown 124. The stand120, the chassis 122, and the crown 124 are all separate components, andmay be coupled with one another via a snap fit, friction fit,interference fit, adhesive, or another method of coupling. As notedabove, the stand 120, the chassis 122, and the crown 124 may allcomprise polypropylene, or another polymeric material. The wires 226 areelectrically coupled with the piezoelectric assembly 110, which isdisposed within the crown 124. A wire tube guide 228 is further disposedwithin the stand 120, which is situated to retain the wire tube 222within the stand 120. The wire tube guide 228 may comprise a horizontalportion having a cutout that retains the wire tube 222 in a staticconfiguration. As further shown in FIG. 13, the piezoelectric assembly110 is centrally located along the longitudinal axis 80. While the stand120, the chassis 122, the platform 118, the base 56, and the shroud 54are illustrated as comprising a polymer, other types of materials arecontemplated.

Still referring to FIG. 13, a plurality of refill retaining ribs 230 aredisposed along an interior of the chassis 122, which may be used toguide the neck 184 of the refill 52 upward, into position within thechassis 122 until the tabs 150 lock into place with the rim 152 alongthe refill 52. A spring 232 is shown, which is used to apply a forceagainst the piezoelectric assembly 110. The spring 232 applies aconstant force against the piezoelectric assembly 110 to retain it in astatic configuration until the refill 52 as it is positioned within thechassis 122 by a user. When a user inserts the refill 52 into thedispenser 50, the piezoelectric assembly 110 is translated upward,causing the spring 232 to compress. The spring 232 defines a spring wire234 that has a wire diameter, which is further discussed below. One ofthe tabs 150 is also shown, the tab 150 including an inwardly-dependingcatch 236 that is configured to translate outward, away from thelongitudinal axis 80 as the refill 52 is being inserted into the chassis122, and snaps back inward to secure the refill 52 in place within thechassis 122 by engaging with the rim 152 (see FIG. 20). Thepiezoelectric assembly 110 is disposed above a refill cavity 240, and isconfigured to receive the distal end 204 of the wick 188 when the refill52 is inserted into the chassis 122.

Referring now to FIG. 14, another cross-sectional view of the dispenser50 is shown. The wire guide 228 and the wires 226 are shown incross-section, and a plurality of LEDs 218 are shown being disposedabove the PCB 216. Further, additional refill guide ribs 230 are shown,which partially define a profile of the head 176 of the refill 52, andare configured to snugly receive the refill 52 within the chassis 122.The spring 232 comprises a top end 242 and a bottom end 244. Thepiezoelectric assembly 110 is also shown in FIG. 14, and is disposedbelow the bottom end 244 of the spring 232. The bottom end of the spring232 may be fixedly attached with the piezoelectric assembly 110, or maybe separate but disposed in physical contact with one another.

The bottom end 244 of the spring 232 is formed to receive thepiezoelectric assembly 110, which is in turn formed to receive the upperwick 194 when the refill 52 is engaged therewith. The top end 242 of thespring 232 is wrapped around and secured to the cylindrical wall 164 ofthe crown 124. The chassis 122 includes an outer ledge 250 that isengaged with an inner ledge 252 of the crown 124. The chassis 122 andthe crown 124 are snap fit together, however, the chassis 122 and thecrown 124 may be coupled together in another fashion, such as viaadhesive, fasteners, an interference fit, or a friction fit. Fastenerwalls 254 defining two of the fastener channels 214 are also shownclearly in FIG. 14, the fastener walls 254 extending between the bottomwall 92 of the base 56 and the platform 118.

Referring to FIG. 15, the printed circuit board (PCB) 216, the wireguide 222 and the piezoelectric assembly 110 are shown in an isometricview. A controller 246 and a timer 248 are shown in schematic view alongthe PCB 216. The controller 246 may be a microcontroller, and may bedisposed within or along the PCB 216. The controller 246 may also be aseparate component that is electrically coupled with the PCB 216. Thetimer 248 may further be disposed within or along the PCB 216, or may bea separate component. The timer 248 is used to time when the dispenser50 is activated, while the controller 246 is operable to receiveinstructions from the buttons 96, 98, 100 to activate the piezoelectricassembly 110, the timer 248, and/or the LEDs 218. As noted above, thePCB 216 is disposed between the base 56 and the platform 118, which areboth removed from the view of FIG. 15 for clarity.

The LEDs 218, the buttons 96, 98, 100, the switches 220, and the wires226 are shown clearly in the view of FIG. 15. A limit switch 256 isfurther shown, which provides a signal to the controller 246 that theshroud 54 has been secured to the base 56, and does not allow thedispenser 50 to be activated until the shroud 54 has been secured to thebase 56. In some embodiments, there is no limit switch 256. The terminal224 is further shown disposed along the PCB 216. Other electricalcomponents, such as resistors, transistors, capacitors, processors,controllers, and relays may further be disposed along or within the PCB216. In some embodiments, a plurality of batteries (not shown) may beenclosed within a casing (not shown) and may be electrically connectedto the PCB 216 for providing electrical power to the PCB 216 and otherelectrical components of the dispenser 50.

Referring to FIG. 16, a top view of the PCB 216 is shown with the wireguide 222 and the piezoelectric assembly 110 having been removed forclarity. The switches 220 are shown in greater detail, and are shownpositioned adjacent each of the first button 96, second button 98, andthird button 100. Further, three sets of three LEDs 218 each are shownin detail in a triangular configuration along the PCB 216. The differentsets of LEDs 218 may emit different colored lights, or may emit the samecolor. Further, the LEDs 218 may have the same intensity or a differentintensity from one another. The port 104 is further shown along the PCB216 at an opposite end of the second button 98. The PCB 216 has agenerally circular profile, however, the PCB 216 may have any profilethat allows it to be securely retained within the profile of the shroud54.

Referring now to FIG. 17, the piezoelectric assembly 110 is shown ingreater detail, along with the wires 226 and an upper end of the wireguide 222. The piezoelectric assembly 110 includes a piezoelectric plate260 and the piezoelectric element 112 that circumscribes the peripheryof an upper surface 262 of the piezoelectric plate 260. Thepiezoelectric plate may comprise stainless steel, which may be SUS 316Lsteel. When the piezoelectric element 112 is energized, thepiezoelectric plate 260 is caused to expand and contract, therebyreleasing a volatile into the surrounding environment. The piezoelectricplate 260 further includes a central dome 264 that is generally concaveand circular in shape. The piezoelectric assembly 110 includes anapertured section 266, at least a portion of which extends along thecentral dome 264. In an illustrative embodiment, the apertured section266 of the piezoelectric plate 260 includes a plurality of orifices 268having a diameter or at least one width dimension of between about 3microns and about 9 microns, or between about 5 and 7 microns, or about6.5 microns. In other illustrative embodiments, the piezoelectric plate260 includes a plurality of orifices having a diameter of between about3 microns and about 5 microns.

Referring to FIGS. 17 and 18A, the piezoelectric assembly 110, when inuse, is positioned adjacent the wick 188. In illustrative embodiments,the piezoelectric element 112 may be formed as a ring and may be made ofceramic. In alternative illustrative embodiments, the piezoelectricassembly 110 may be formed in any suitable shape and/or may be made ofany suitable material having piezoelectric properties and which causesthe material to change dimensionally in response to an applied electricfield. Illustrative examples of suitable materials include, but are notlimited to, lead zirconate titanate (PZT) or lead metaniobate (PN).While a particular piezoelectric element is described, any actuator maybe utilized, for example, a piezoelectric vibrating mesh actuator, apiezoelectric standing wave actuator, a piezoelectric vibrating needle,or any other suitable piezoelectric actuator.

Referring to FIGS. 18B and 18C, the plurality of orifices 268 along thepiezoelectric plate 260 may define an array 269 that is circular innature. The array 269 of orifices may be defined along the entire dome264, as shown in FIG. 266. The array 269 may alternatively be disposedalong only a portion of the dome 264, or may extend beyond the dome 264,as depicted in FIG. 18C. The array 269 may have alternativeconfigurations, and may be in the shape of a triangle, a square, anoval, or a polygon. Further, the orifices 268 may be in the shape of acircle (FIG. 18B), a rectangle or square (FIG. 18C), or another shape.It should be noted that the orifices 268 depicted in the schematic viewsof FIGS. 18B and 18C do not represent the actual size or actual numberof the orifices 268, rather, the orifices 268 may define dimensions asnoted herein.

In some embodiments, the array 269 has a diameter or at least one widthdimension of between about 0.5 mm and about 10.0 mm, or between about1.0 mm and about 9.0 mm, or between about 2.0 mm and about 8.0 mm, orbetween about 3.0 mm and about 7.0 mm. Referring again to FIG. 12, awick diameter DW and an array diameter DA (see FIG. 18) may define aratio of DA/DW of between about 1.0 and about 3.0. In some embodiments,the ratio is about 1.1. In some embodiments, the wick diameter DW isbetween about 3.0 mm and about 5.5 mm, or between about 3.5 mm and about4.0 mm, or about 3.8 mm. In some embodiments, the array diameter DA isbetween about 3.0 mm and about 6.0 mm, or between about 4.0 mm and about5.0 mm, or about 4.5 mm. The ratio of wick diameters may affect theaccuracy and consistency of the plume of the volatile that is emitted bythe dispenser 50. For example, having a ratio DW/DA of about 1.1 hasbeen found to create a repeatable and accurate dispersal of volatilefrom the dispenser 50. In some embodiments the array 269 may comprisebetween about 100 and about 400 orifices, or between about 150 and about350 orifices, or about 316 orifices, or about 200 orifices.

Referring now to FIGS. 19 and 20, detail views of the upper end of thestand assembly 116 are shown without and with a refill having beeninserted therein, respectively. Referring to FIG. 19, the piezoelectricassembly 110 is shown in greater detail. In some embodiments, a softmaterial, such as loading foam, may be provided along an underside ofthe piezoelectric assembly 110. Additional materials may be providedalong an underside of the piezoelectric assembly 110 to aid in accuracyor consistency of the plume of volatile generated when the dispenser 50is activated. The additional materials may also be provided to enhanceor reduce a dampening effect that could be caused by the spring 232, thewick 188, and/or the piezoelectric plate 260.

The top end 242 of the spring 232 is shown wrapped around thecylindrical wall 164, while the bottom end 244 of the spring 232 isshown in contact with and applying a force against the piezoelectricassembly 110. The chassis 122 further includes a piezo platform 270,which is unitary with the chassis 122 and defines a surface to which thepiezoelectric assembly 110 is secured. The piezo platform 270 retainsthe piezoelectric assembly 110 in place, and prevents the piezoelectricassembly 110 from being displaced farther than the piezo platform 270.The piezo platform 270 is generally circular and includes an aperture272 in a center thereof, which allows the distal end 204 of the wick 188to engage in physical contact with the piezoelectric assembly 110 wheninserted into the chassis 122. The spring 232 is positioned to providean opposing force against the refill 52 when it has been inserted intothe chassis 122. As noted below, when the wick 188 is engaged with thepiezoelectric assembly 110, the spring 232 is compressed and thepiezoelectric assembly 110 is displaced a distance X above thepiezoelectric platform 270. This displacement is discussed in greaterdetail hereinafter below.

Referring to FIG. 20, the refill 52 is shown having been inserted intothe manifold 126. Because the refill 52 has been inserted into therefill cavity 240 of the chassis 122, the spring 232 has beencompressed, thus, the spring 232 is shown in a compressed configuration.Still referring to FIG. 20, the rim 152 of the refill 52 is also shownengaged with the catches 236 of the tabs 150, and the distal end 204 ofthe wick 188 is shown in physical contact with a lower surface 276 (seeFIG. 18) of the piezoelectric assembly 110. The compression of thespring 232 shown in FIG. 20 is a result of the size and type of springthat is used in the dispenser 50, which may be chosen based upon avariety of factors, as discussed below. Other than the spring 232 havingbeen compressed, the piezoelectric assembly 110 having been translatedupward due to the force applied by the wick 232, and the catches 236 ofthe tabs 150 having been engaged with the rim 152 of the refill 52, noother elements of the manifold 126 are moved or manipulated when therefill 52 is inserted into the manifold 126. FIG. 20 shows the refill 52in an operational state, where the dispenser 50 could be activated todisperse the volatile by providing an electrical pulse to thepiezoelectric assembly 110.

In illustrative embodiments, and as noted above, an absorbent material(not shown) may be included between the wick 188 and the piezoelectricassembly 110. The absorbent material may be a felt pad and/or cottonwool. In other illustrative embodiments, the absorbent material may beformed of a velour pad, cotton cloth, chenille yarn, chenille fabric,polyester cloth, paper towel, synthetic cloth, synthetic nonwovenmaterial, a cotton ball or swab, combinations thereof, or other suitableabsorbent material(s). The absorbent material may be a component of thenebulizer assembly or may be attached or otherwise in communication withthe wick 188 of the refill 52.

During operation, the piezoelectric assembly 110 is actuated, eithercontinuously or intermittently, to dispense volatile material. Moreparticularly, an oscillating electric field is applied to thepiezoelectric element 112, which causes expansion and contraction of thepiezoelectric plate 260 in a radial direction. The expansion andcontraction causes the piezoelectric plate 260 to vibrate in an axialdirection (along a longitudinal axis of the dispenser 50), forcingvolatile material retained within the orifices of the piezoelectricplate 260 away from the piezoelectric assembly 110, through a channel280 defined by the cylindrical wall 164, and through the chimney 78 ofthe shroud 54.

Referring to the graph of FIG. 21, three separate groups of springs weretested as the spring 232 in the dispenser 50 described above, theresults of which are illustrated in the figure. The three groups ofsprings comprise spring wires 226 having a diameter of 0.50 mm, a springhaving a diameter of 0.55 mm, and a spring having a diameter of 0.60 mm.The graph illustrates a spring force measured in Newtons (N) against aspring compression distance measured in millimeters (mm). The springcompression distance is the distance X noted above, i.e., a distancebetween the piezoelectric platform 270 and the piezoelectric assembly110 after the wick 188 causes the piezoelectric assembly 110 to betranslated upward. The graph further illustrates a minimum, an average,and a maximum for each of the three springs. Testing involvediteratively compressing springs from 1.0 mm to 8.0 mm while recordingthe resulting force output (N). While the three different springdiameters, i.e., 0.50 mm, 0.55 mm, and 0.60 mm, achieved differentresults, the results suggest that at a compression of 7.0 mm, each ofthe three springs saw a non-linear increase in measured spring force.

In some embodiments, the spring 232 may have an uncompressed height ofbetween about 7 mm and about 20 mm, or between about 10 mm and about 17mm, or about 13 mm. Further, in some embodiments, the spring 232 mayhave between about 2 turns and about 10 turns, or between about 3 turnsand about 7 turns, or about 4.5 turns. In a preferred embodiment, thespring 232 has a spring wire diameter of about 0.6 mm, an uncompressedheight of about 13 mm, and comprises about 4.5 turns.

Referring now to the graph of FIG. 22, the spring force measured inNewtons (N) against a fragrance output measured in milligrams per cycle(mg/cycle) is shown. The graph illustrates results from the testingdisplayed in FIG. 21. The results of the tests suggest that thedispenser 50 emits a greater volume of fragrance when the springs inducelower compressive forces upon the piezoelectric plate 260. Fragranceemission patterns can be simplified into a first linear region 284 and asecond linear region 286. The first region 284 occurs between 0.6 and0.9 N and has an approximate slope of −25 mg/cycle/N. The second region286 occurs between 0.9 and 2.0 N and has an approximate slope of −8.33mg/cycle/N. The results suggest that the fragrance device emits a largervolume of fragrance when subjected to lower spring forces. As a result,depending on the desired range of outputs, a particular spring may beidentified for use with the dispenser 50. To that end, the 0.50 mm or0.55 mm spring would likely be utilized if one desired to achieve afragrance output within the first linear region 284 and the 0.60 mmspring would likely be utilized if one desired to achieve a fragranceoutput within the second linear region 286.

Based on the testing, it was determined that having an upper wick 192with a more pliable material causes less displacement of the spring 232that applies a force against the piezoelectric assembly 110, whichresults in a more predictable dispersal of volatile. The variability ofthe dispensed plume is more predictable when operating within the linearregion, while the variability of the release rate increasessignificantly when the force displacement of the spring 232 isnon-linear. It has also been found that the amount of force that isapplied by the spring 232 against the piezoelectric assembly 110 has adirect correlation with the release rate of the volatile. The lower theforce, the more the piezoelectric assembly 110 can bounce within thechannel 280.

Referring to FIGS. 23-25, a method of inserting the refill 52 into thestand assembly 116 and assembling the dispenser 50 are depicted.Referring to FIG. 23, the refill 52 is positioned with the head 176thereof being inserted into the manifold 126. The lower wall 180 of therefill 52 is slid through the slot 142 of the platform 118 and therefill 52 is moved upward so that the head 176 is inserted into themanifold 126. Referring to FIG. 24, once the rim 152 of the refill 52has been engaged with the catches 236 of the tabs 150, the refill 52 canbe characterized as being secured within the manifold 126. The cap 146of the refill 52 may be inserted into the well 138 to securely retainthe cap 146 while the refill 52 is in use. Referring to FIG. 25, theshroud 54 is aligned with the base 56 and is rotated until theprotrusions 128 along the base 56 engage with features along theunderside 162 of the shroud 54. The shroud 54 may alternatively beengaged with the base 56 in another way. Once the shroud 54 has beencoupled with the base 56, one end of a power cord (not shown) is pluggedinto the port 104 and the other end is plugged into a power source suchas a power adapter, a laptop, or another low voltage outlet.

Still referring to FIG. 25, the first button 96 is a power button, thesecond button 98 is a fragrance strength button, and the third button100 is a light button. The first button 96 may be pressed once to turnthe dispenser on. The dispenser 50 will begin to dispense fragrance oncethe first button 96 has been depressed. The second button 98 and thethird button 100 may be pressed to personalize the preference of thefragrance strength and/or the light scheme. During operation of thedispenser 50, it is desirable to have the wick 188 in contact with thepiezoelectric plate 260. If the wick 188 is not in contact with thepiezoelectric plate 260, especially in a water-based fragranced volatilematerial, the dispenser 50 may not function properly and/or may not emitvolatile material at all.

Any of the embodiments described herein may be modified to include anyof the structures or methodologies disclosed in connection with otherembodiments. Further, although directional terminology, such as front,back, upper, lower, vertical, horizontal, etc. may be used throughoutthe present specification, it should be understood that such terms arenot limiting and are only utilized herein to convey the orientation ofdifferent elements with respect to one another.

INDUSTRIAL APPLICABILITY

Dispensers are commonly used to dispense a variety of volatile materialssuch as air fresheners, deodorants, insecticides, germicides, perfumes,and the like, that are stored within refill containers. Piezoelectricengines allow the volatile materials to be volatilized and thendistributed into an environment in order for the contents thereof to bereleased without human interaction, for example, continuously oraccording to a predetermined time schedule

We claim:
 1. A volatile material dispenser, comprising: a base thathouses a printed circuit board; a stand assembly that is coupled withthe base via one or more fastening mechanisms, the stand assemblyincluding a platform, a stand that extends from the platform, and amanifold that extends from the stand; and a refill that is removablycoupled with the manifold, the refill comprising a wick that defines awick diameter (DW), wherein the manifold houses a piezoelectric elementthat defines an array of apertures and the array defines an arraydiameter (DA), and wherein a ratio of the wick diameter and the arraydiameter (DW/DA) is greater than 1.0.
 2. The volatile material dispenserof claim 1, wherein the base further includes a low voltage port that iscapable of being electrically coupled with a low voltage power source.3. The volatile material dispenser of claim 1, wherein a plurality ofLEDs are coupled with the printed circuit board.
 4. The volatilematerial dispenser of claim 3, wherein the plurality of LEDs areconfigured to display a first color and a second color.
 5. The volatilematerial dispenser of claim 1, wherein the manifold comprises a chassisand a crown, the crown comprising a cylindrical wall that defines achannel, and a shroud coupled to the stand assembly, wherein the shrouddefines a chimney that is coaxial with the channel.
 6. The volatilematerial dispenser of claim 1, wherein the piezoelectric elementincludes a piezoelectric plate, and wherein the piezoelectric plateincludes a dome, the array of apertures being entirely disposed alongthe dome.
 7. The volatile material dispenser of claim 1, wherein thearray of apertures are disposed in a circular array.
 8. The volatilematerial dispenser of claim 1 further comprising a limit switch disposedalong the PCB, and wherein the limit switch prevents activation of thepiezoelectric element unless a shroud is coupled with the standassembly.
 9. A volatile material dispenser, comprising: a base thathouses a printed circuit board; a stand assembly that is coupled withthe base, the stand assembly including a platform, a stand that extendsfrom the platform, and a manifold that extends from the stand, themanifold containing a circular piezoelectric element; a shroud that iscoupled with the stand assembly and defines a chimney; and a refillcomprising a wick, the refill being removably coupled with the manifold,wherein the manifold includes a cylindrical wall that extends from themanifold, wherein a spring is disposed within the manifold and iscoaxial with the cylindrical wall, and wherein a top end of the springis wrapped around the cylindrical wall and a bottom end of the springapplies a force against the piezoelectric element.
 10. The volatilematerial dispenser of claim 9, wherein the spring has a spring wire witha diameter of between about 0.50 mm and about 0.60 mm.
 11. The volatilematerial dispenser of claim 9, wherein a first tab and a second tabdepend from the manifold to receive a refill.
 12. The volatile materialdispenser of claim 11, wherein the first and second tabs include firstand second catches that extend inward, and are capable of engaging witha rim of the refill.
 13. The volatile material dispenser of claim 9,wherein the spring causes a force to be exerted against a head of arefill when the refill is inserted into the manifold.
 14. The volatilematerial dispenser of claim 9, wherein the piezoelectric element definesan array of apertures and the array defines an array diameter (DA), andwherein a ratio of a wick diameter (DW) and the array diameter (DW/DA)is about 1.1.
 15. The volatile material dispenser of claim 9, whereinthe manifold defines a head cavity, and wherein a plurality of ribsextend from the manifold into the head cavity.
 16. The volatile materialdispenser of claim 9, wherein the manifold comprises a chassis and acrown that is snap fit to the chassis.
 17. The volatile materialdispenser of claim 16, wherein a plurality of ribs extend along a sidesurface of the crown that are physically engaged with an underside ofthe shroud.
 18. A volatile material dispenser, comprising: a base thathouses a printed circuit board, the base defining a sidewall, andincluding at least one button that projects from the sidewall and a lowvoltage port; a stand assembly that is coupled with the base; a shroudhaving a frustoconical sidewall that has a lower edge that extends froman upper edge of the base, the shroud defining a chimney; and a refillcomprising a wick, the refill being removably coupled with the standassembly, wherein the at least one button is disposed about 180 degreesoffset from the low voltage port.
 19. The volatile material dispenser ofclaim 18 further including a spring within a manifold of the standassembly, the spring being operable to engage with the piezoelectricelement to maintain continuous contact between the wick and thepiezoelectric element, wherein the spring has a spring wire with adiameter of between about 0.50 mm and about 0.60 mm.
 20. The volatilematerial dispenser of claim 18, wherein the piezoelectric elementdefines an array of apertures having an array diameter (DA), and whereinthe wick defines a wick diameter (DW), wherein a ratio of the wickdiameter to the array diameter (DA/DW) is greater than 1.0.